Why was Kasey Kahl smiling in his mug shot?

Fans of The Bachelorette and Bachelor Pad were floored when show veteran Kasey Kahl, 27, was arrested and booked for drunk and disorderly conduct after a bar fight in Fresno, California.

Even more confusing? The wide smile in his official mug shot.

Was the ex-boyfriend of Vienna Girardi really that drunk? No, he claims. “I was really friendly, and I knew what was going on wasn’t what it was in its entirety,” the reality star told People of his Jan. 15 arrest.

“I wasn’t drunk. I smiled. I wasn’t charged with anything. I wasn’t convicted of anything. There were no charges filed. I just smiled because [jail personnel] told me to.”

However, that’s about as much as he’ll reveal about the arrest.

“I can’t talk about the incident or the allegations,” Kahl told the magazine. “The truth will be out there. I know that in my heart I did nothing wrong.”

At the time, his rep claimed that his assailants just wanted some publicity.

“We would not be surprised if these persons bent on attaining their 15 minutes of fame, while intoxicated and perhaps fueled by jealousy, will antagonize and attack stars such as Kasey in a Jersey Shore type brawl given the opportunity,” Richard Harlow said.

“These persons wanted their 15 minutes, which they received, and now those 15 minutes are over. The recent reports emphasizing any brutality on his behalf and downplaying his act of self-defense are entirely speculative and false.”

So, we’re assuming he’s not going to make a habit of happy-go-lucky jailhouse poses.

“I was having a good time with cops,” he added. “They were joking around.”